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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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Controlling tunneling in ammonia isotopomers
Csaba Fábri1, Roberto Marquardt2, Attila G Császár1
1Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary.
The Journal of Chemical Physics
|January 10, 2019
Summary
Quantum dynamics simulations reveal control over ammonia isotopomer tunneling. Laser fields can inhibit or enhance stereomutation, offering insights into molecular behavior.
Area of Science:
- Quantum chemistry
- Molecular dynamics
- Spectroscopy
Background:
- Understanding molecular dynamics is crucial for predicting chemical reactions and properties.
- Ammonia isotopomers exhibit complex tunneling and stereomutation behaviors.
- Quantum control offers a pathway to manipulate molecular processes.
Purpose of the Study:
- To investigate the quantum dynamics of ammonia isotopomers.
- To explore the control of tunneling and stereomutation using laser fields.
- To develop a theoretical framework for time-dependent quantum simulations.
Main Methods:
- Full-dimensional variational rovibrational quantum-dynamical computations.
- Solution of the time-dependent Schrödinger equation for nuclear motion.
- Inclusion of coherent infrared multiphoton excitation.
Main Results:
- Accurate rotational-vibrational levels for NH2D, NHD2, NHDMu, and NHDT.
- Time-dependent probability densities and wavepacket evolution.
- Demonstration of laser-induced inhibition and enhancement of stereomutation.
- Time-dependent chirality analysis for NHDT.
Conclusions:
- The developed computational framework enables precise control over molecular tunneling.
- Laser fields can selectively inhibit or enhance stereomutation dynamics in ammonia isotopomers.
- Quantum dynamics simulations provide deep insights into molecular behavior and control.
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